Engine driven generator system



F. BRACKEN ET AL ENGINE DRIVEN GENERATOR SYSTEM Oct. 31, 1939.

Filed Nov. 19, 1937 2 Sheets-Sheet 1 INVENTORS fbA/vK BIPACKEN BU$5ELLP550 ATTORNE Oct. 31, 1939. BRACKEN ET AL 2,177,686

ENGINE DRIVEN GENERATOR SYSTEM Filed Nov. 19. 1957 2 Sheets-Sheet 2 a/.v l/Z //2 I #5111 1/7 11 1 o I l0:

INVENTORS FI'PA/VK BRACKEN fuasru. FEED ATTORNEE Patented Oct. 31, 1939UNITED STATES ENGINE DRIVEN GENERATOR SYSTEM Frank Bracken and RussellReed, Los Angeles, Calif., assignors to Warner Bros. Pictures, Inc., NewYork, N. Y., a corporation of Delaware Application November 19, 1937,Serial No. 175,442

16 Claims.

This invention relates to engine driven generator units, and has thefollowing objects: to reduce the noise of an internal combustion engineand associated mechanism; to reduce the noise of exhaust gases of aninternal combustion engine; to direct the noise of an engine assembly ina predetermined path; to increase the efficiency of a cooling system foran engine; to increase the flow of air in a cooling system for aninternal combustion engine; and to produce a compact engine assembly.

The manner in which the above and other objects of the invention isaccomplished will be apparent from the following specification read inconjunction with the accompanying drawings wherein:

Fig. 1 is a sectional, elevational view through an engine drivengenerator assembly embodying the present invention.

Fig. 2 is a sectional plan view of the generator assembly and is takenalong the lines 22 of Fig. 1.

Fig. 3 is an end View of the generator assembly with the rear panelremoved and is taken in the direction of the arrow 3 of Fig. 1.

Fig. 4 is a perspective view of the rear of the generator assembly.

Fig. 5 is a sectional, elevational view of the fan drive and is takenalong the line 55 of Fig. 2.

Fig. 6 is a sectional view, partly broken away, of one of the waterjacketed exhaust manifolds.

Fig. 7 is a sectional View through the generator assembly, partly brokenaway, showing a modified form of fan drive.

Referring particularly to Figs. 1, 2 and 3, the engine-generatorassembly comprises an electric generator generally indicated at l0 and agasoline engine of the V-type generally indicated at The generator I0 isof the usual construction comprising a circular casing |2 enclosing boththe field coils (not shown) and the armature l3. The armature shaft l3of armature I3 is rotatably carried at one end thereof in an outboardbearing l4 supported from the casing I2 through a spider shaped bracketl5.

The gasoline engine II is also of the usual construction comprising acrankcase l6 and a pair of cylinder blocks [1 and I8 secured thereto ina V-formation. The crank shaft IQ of the engine II is suitably connectedin a manner not shown to the armature l3 for rotating the same. A flangeat the rear of the engine [I is secured to the generator Ill throughbolts 2|, forming an integral engine-generator unit.

The rear of the engine-generator unit is supported by means of wheels 23and 2d. Respective shafts 23 and 2 3 of wheels 23 and 24 are carried bybrackets 25 and 26, respectively, secured on either side of thegenerator casing H by bolts 21.

A sub chassis is provided to support the forward end of theengine-generator unit on a single steerable wheel l8. This chassiscomprises a pair of longitudinally extending channel members 3i! and 3|on either side of the crankcase [6 of engine Each of the channel membersand 3| are secured to the sides of the crankcase I6 by a series of bolts32. A cross bar 33 is secured across the members 36 and 3| by bolts 34and has formed in the center thereof a vertically extending bearing torotatably receive an upwardly extending bearing stud 35 projectingfrom awheel saddle 3G. Saddle 36 has secured to the lower ends thereof theshaft 3i of wheel 28. A draw bar 38 is secured to the shaft 37 for thepurpose of moving and steering the unit.

The forward ends of the channel members 3|] and 3|, forming part of thesub-chassis, are secured, as by welding, to a cross piece 40 formingpart of a panel frame 39. Longitudinally extending frame beams 4| and42, also forming part of the panel frame 39 are secured at either end ofthe cross piece 40. The opposite ends of the members 4| and 42 arewelded to a second cross piece 43. The rear section of the panel frame39 is supported from the generator |2 through brackets 44 and 45, (Fig.3) which brackets secure the cross bar 43 to the spider bracket l5 ofthe generator l2 by bolts 46. Vertical corner posts comprisingstructural angles ll, 48, 49 and 50, also forming part of the panelframe 39 are suitably secured at their lower ends to the corners of therectangular frame comprising the members 49, 4|, 32 and 43. Structuralties 5|, 52, 53 and 54 completing the panel frame 39 are secured betweenthe upper ends of the corner posts 4'! to 50, inclusive.

A series of sound insulating panels 55, 56, 51 and 58, enclosing thesides of the panel frame 39, form an enclosure open at its bottom andtop ends to form an air and sound conduit therethrough. Each of thesepanels comprises an outer sheet of metal 59 and an inner sheet of soundabsorbing and fireproof material 59 such as asbestos, secured thereto toreduce the transmission of sound therethrough.

An air cooled heat radiating water radiator 60 is suitably secured inthe upper end of the panel frame and substantially fills the same. Theradiator E30 slopes downward slightly, for example, at the front endthereof to permit a drainage of the water therein toward the front ofthe unit. A protective Wire screen of wide mesh Si is supported abovethe surface of the radiator '80 to prevent damage to the radiator fromfalling objects. The position of the radiator in a horizontal positionnot only permits it to be cooled in part by the natural convection ofair but results in a more unitary and compact structure for the sameamount of radiator surface. Furthermore, the radiator is situated in asafe and unobstructing position permitting ready access to all parts ofthe generator and motor.

The water cooling system for the engine II comprises a water pump 62having an inlet 03 and an outlet 64, which pump is driven by a suitablemotor 65. Pump 62 may also be coupled to the cam shaft of engine II. Theinlet 63 is connected to the outlet end of the radiator 60 through aninlet pipe 86. Flexible hose couplings 61 and 68 are provided toresiliently support the pipe 66 between the inlet 63 of pump 62 and theoutlet 89 of the radiator 00 to prevent breakage thereof clue tovibration or misalignment of the radiator 50 relative to the engine II.The outlet 54 of the water pump 62 is connected through a flexible hosecoupling 09 to a T I0. One end of the T I0 is connected to the watercooling passages (not shown) of the cylinder block I8 through aconnection 9%. The other end of the T I0 is connected through a conduitll, passing through the crankcase IE, to a connection 9I (Fig. 3)communicating with the water cooling passages in the opposed cylinderblock I'I. After passing through the water cooling passages of thecylinder blocks I1 and I8, the water is passed through short conduits I2opening into water jackets I4 and i5, respectively. Return conduits I6and TI are connected between the water jackets I4 and 75, respectively,and the rear end of the radiator 60 to return the heated Water to theradiator for cooling.

The water jackets I4 and I5 enclose a portion of the exhaust manifoldsI8 and I9, respectively, which are connected through conduits (Fig. 6)to the interiors of the exhaust chambers of the respective cylinderblocks. The manifolds I8 and I9 pass above the radiator 60 and open intoseparate sound absorbing mufflers 8| and 82, respectively.

The radiator 50 is cooled by a series of fans 83, 84 and 85. The fan 83is driven from the cam shaft of the engine I I through a gear unitgenerally indicated at 86 (Fig. 5). Unit 86 comprises a pair of beveledgears 81 and 88, the gear 08 being secured to the end of the cam shaft09 of motor II. The gear 87 is secured to the lower end of a shaft 90journaled within bearings SI and 92 formed in upper and lower gearcasings 93 and 94, respectively. The upper gear casing 93 is supportedfrom the lower casing 94 by a tubular column 73. The pinion gear 95,secured to the upper end of the shaft 90, meshes with a gear 96, securedto the fan shaft 91. The shaft 91 is journaled within bearings formed inthe upper gear casing 93 and has secured thereto a belt pulley 98adapted to drive a continuous belt 99. The fans 84 and are secured tovertically extending shafts I00 and I iiI, respectively, journaledwithin columns I 02 and I03, respectively. The column I 03 is secured tothe upper surface of the casing I2 of generator I0, while the column I02is secured to a cross plate I04 (Fig. 2) suitably supported between thetwo cylinder blocks I1 and I8. Pulleys I05 and I06 are secured to thefan shafts I00 and NH, respectively.

A modified form of fan drive is shown in Fig. '7 wherein the fans 85etc. are driven from the generator shaft I3 instead of from the camshaft 89 of engine II. In this case the casings 93, 94 and column 13(Figs. 1 and 5) are retained merely to provide bearings for the fanshaft 91, the shaft and gears associated therewith being removed. Apulley II4 (Fig. 7) is secured to the end of generator shaft I3 to drivean endless belt II5. Belt II5 travels over a pair of coaxial idlerpvlleys, one of which is shown at H5, and around a pulley III, securedto the fan shaft H of fan 85. A bracket IIB rotatably supports theco-axial idler pulleys from the top of generator casing I2.

In lieu of the above mentioned arrangements for driving the fans 83, 84and 85, an electric motor may be substituted, deriving its current fromthe output circuit of the generator I0.

It will be noted on reference to Fig. 2 that the shaft I90 of fan 84 isdisposed out of line with the centers of the other fans 83 and 85whereby a sufiicient amount of arcuate contact of the belt $9 on thepulley I05 is formed to insure a driving traction.

Mufflers 8I and 82 are supported above the radiator 60 on cross beams H0and III. These beams are supported at their ends on the longitudinallyextending upper frame members 52 and 54, forming part of the panel frame39. Semicircular straps II2 secure each of the mufflers BI and 82 to thecross beams H0 and III by bolts H3.

The transmission of sound from a medium of a certain density to anothermedium of a different density will cause reflection and refraction ofthe sound to be set up at the juncture of the two mediums. Furthermore,the amount of reflection depends on the difference in density betweenthe mediums through which the sound is passed, it being greater forgreater differences in density. The mufflers BI and 82 are arranged toutilize the above principle by spacing them apart, closely adjacent theedges of the side panels 55 and 56. Also the mufflers are arrangedparallel with each other. Now, when the bank of heated air, carryingwith it the engine noises, is forced upwardly through the radiator 60 bythe fans 83, 04 and 85, it passes in contact with the mufflers BI and82. Therefore. this bank of heated air will be further heated along thesides thereof due to its contact with the hot mufiiers which are in turnheated by the exhaust gases passing therethrough from the en gine I I.Thus it will be seen that the density of the heated air bank which isreduced due to the heat thereof will be further reduced along the sidesthereof because of additional heating imparted by the mufflers 8I and82. Consequently, a greater change in density will be effected at theboundary of the heated air bank and the outer cool air resulting in agreater reflection and refraction of the sound Waves Within the airbank. This reflection and refraction of the sound waves will continueback and forth across and within the air bank as it is rising upwardlyfrom the generator unit thereby substantially confining the noise withinthe heated air bank and reducing the horizontal transmission of soundoutside of the heated air bank.

Whether the above explanation is correct or not, the fact is that wehave successfully demonstrated that the method and means hereindisclosed provide a much quieter generator unit than heretofore.

However, there is support for our view that a material part of thereduction of the various noises of the engine and generator is caused bythe absorption of sound by the heated air through which the variousnoises pass.

As will be noted in Figs. 1 and 3 the outlet conduits H4 and H5 of themufflers 8| and 82, respectively, are returned to a central positionrelative to the radiator 60 and terminate in an upwardly extendingposition to direct the exhaust gases upwardly in the rising aircurrents. The exhaust of the exhaust gases in an upward direction aswell as the heat produced by the mufliers 8| and 82 increases thenatural convection of air through the enclosure formed by the variouspanels 55 to 58, inclusive, thereby reducing the transmission of exhaustand engine noise in a horizontal direction.

Due to the position of the mufflers within the vertically rising currentof air caused by the fans 83, 84 and 85, as well as due to the naturalconvection thereof, these mufflers will be cooled, thus reducing theexpansion of exhaust gases therein and consequently reducing the noisecaused by these gases.

The cooling of the exhaust manifolds by means of the water jackets M and15 insures a minimum of heat being generated within the enclosure formedby the panels 55 to 58, inclusive, while reducing the expansion of thegases within these manifolds with a consequent reduction in sound in theexhaust.

The particular arrangement of the radiator to above the motor H andgenerator 52 and the provision for directing the air upwardly in avertical direction permits both the engine and particularly thegenerator to be cooled by the air passing upwardly through the enclosurebefore it is warmedby passage through the radiator. This particulararrangement also insures that all parts of the engine-generator unit aswell as the radiator 60 are equally exposed to the draft of cooling air.Furthermore, the use of a plurality of fans insures a uniform cooling ofthe entire surface of the radiator 60 while permitting a relatively slowperipheral speed of each fan to obviate the noisy whirl caused by thefan blades at high speed.

The invention is particularly applicable to portable engine drivengenerator units for use in supplying current to lamps, motors, etc. usedin photographing motion pictures while recording the sound incidentthereto. However, it is to be understood that the invention has numerousother fields of application. Further, while we have illustrated anddescribed our invention in its preferred embodiment, it is to beunderstood that various modifications may be made and no limitationsupon the invention are intended other than are imposed by the scope ofthe appended claims.

We claim:

1. A motor assembly comprising an internal combustion motor, a soundmuffler, means for conveying exhaust gases from said motor to saidmufiier, and a radiator for said motor intermediate said motor and saidmufiler.

2. A motor assembly comprising an internal combustion motor, a soundmuffler, means for conveying exhaust gases from said motor to saidmuffler, a heat dissipating radiator for said motor intermediate saidmotor and said muffler, and

means for directing air past said motor, through said radiator, andthence past said mufiler.

3. A motor assembly comprising a water cooled internal combustionengine, a muffler, means for conveying exhaust gases fromsaid engine tosaid muflller, a water cooling radiator intermediate said engine andsaid muffler, means for conveying Water between said radiator and saidengine for cooling said engine, and means intermediate said radiator andsaid engine for passing air through said radiator from said motor andpast said muffler.

4. A motor assembly comprising an internal combustion engine, avertically extending enclosure surrounding said engine and having anopening at the lower end thereof, a radiator for said engine at theupper end of said enclosure, and means for directing air upwardly insaid enclosure past said engine and thence through said radiator.

5. A motor assembly in accordance with claim 4 wherein said enclosurecomprises sound absorbing material.

6. A motor assembly comprising a fluid cooled internal combustion motor,a vertically extending i enclosure surrounding said motor and having anair inlet at its lower end below said motor, a horizontally disposedfluid cooling radiator in said enclosure above said motor, means forconveying fluid between said radiator and said motor for cooling saidmotor and means for directing air upwardly through said air inlet andthrough said enclosure and said radiator.

'7. A motor assembly comprising a water cooled internal combustionmotor, a vertically extending enclosure surrounding said motor andhaving the lower end thereof open, a horizontally extending watercooling radiator at the upper end of said enclosure for cooling saidmotor. means for conveying water between said radiator and said motor, amuffler adjacent the upper surface of said radiator, means for conveyingthe exhaust gases from said motor to said muffler, and means fordirecting air upwardly through the lower open end of said enclosure andthrough said radiator and past said muilier.

, 8. A motor assembly comprising a water cooled internal combustionmotor, a sound proof enclosure surrounding said motor and having thelower end thereof open, a horizontally disposed water cooling radiatorat the upper end of said enclosure for cooling said motor, means forconveying water between said radiator and said motor, a muffler aboveand adjacent said radiator, means for conveying the exhaust gases fromsaid motor to said muflier, means for causing a flow of air currentsupwardly in said enclosure past said motor, through said radiator andpast said muffler, and means independent of said last mentioned meansfor directing the exhaust gases emerging from said muffler upwardly insaid currents.

9. A motor assembly comprising a fluid cooled internal combustion motor,an enclosure surrounding said motor and having an air inlet at the lowerend thereof and an outlet at the upper end thereof, a sound mufiier,means for conveying exhaust gases from said motor to said mufiler, aradiator for said motor intermediate said motor and said muffler andmeans for directing air currents from said inlet upwardly through saidenclosure and through said outlet.

10. A motor assembly comprising an internal combustion motor, avertically extending enclosure surrounding said motor and having an airinlet at the lower end thereof and an outlet at the upper end thereof, amuilier adjacent said outlet above said motor in line with saidenclosure and means for causing a flow of air upwardly in said enclosurefrom said inlet around said motor and past said mufiler.

11. A motor assembly comprising a fluid cooled internal combustionmotor, a vertically extending enclosure surrounding said motor andhaving an air inlet at the lower end thereof, a horizontally disposedfluid cooling radiator in said enclosure above said motor, means forconveying cooling i'iuid between said radiator and said motor, a pair oflaterally spaced mufflers above and adjacent said radiator, means forconveying exhaust gases from said motor through said muillers, and meansfor directing air upwardly through said enclosure and said radiator,said mufilers lying in the path of said air and defining a spacetherebetween to permit the major portion of said air to pass upwardlybetween said muiiiers.

12. The combination of an engine, a vertically extending sound proofenclosure surrounding said engine and having an air inlet at the lowerend thereof below said engine and an outlet at the upper end thereof,fan means for creating a draft of air from the inlet to the outlet ofsaid enclosure, and means at said outlet for heating the air dischargedtherethrough with the exhaust from said engine.

13. The combination of an engine, an enclosure having substantiallyvertical side walls surrounding said engine, said enclosure beingdiscontinuous at the top and bottom thereof, the bottom of saidenclosure serving as an inlet and said top serving as an outlet for aventilating stream of air, means for supporting an engine in the bottomof said casing, said means and said engine only partially closing thebottom of said enclosure, a radiator extending between the side walls ofsaid enclosure at the top thereof, a plurality of laterally spaced fansunderneath said radiator and above said engine, means for rotating saidfans, and means for supporting said enclosure above the floor.

14. The combination according to claim 13 comprising a pair of laterallyspaced mui'llers for said engine above said radiator, and meansassociated with the walls of said enclosure for supporting said muiilersadjacent said radiator.

15. The combination of an engine, a chassis, means for securing saidengine to said chassis, a. plurality of panels of sound deadeningmaterial forming an enclosure for said engine, means for supporting saidpanels from said chassis, means for supporting said chassis above thefloor, said chassis being discontinuous to permit a stream ofventilating air to be passed through said chassis and around saidengine, a radiator at the top of said enclosure, and ventilating fanmeans between said radiator and said engine.

16. A motor assembly comprising a water cooled internal combustionmotor, a vertically extending enclosure surrounding said motor andhaving the lower end thereof open, a horizontally extending watercooling radiator at the upper end of said enclosure for cooling saidmotor, means for conveying water between said radiator and said motor, amufiler adjacent the upper surface oi said radiator, means for conveyingthe exhaust gases from said motor to said muiiler, and fan meansinteri'l'iediate said motor for directing air upwardly through saidenclosure and said radiator and past said muffler,

FRANK BRACKEN. RUSSELL REED.

